Practical tie-breaking for parallel/distributed simulations

In this paper, we discuss a tie-breaking strategy based on a bitwise comparison of event payload that allows parallel and distributed discrete-event simulations to observe a deterministic order in the execution of events, even in the presence of event ties. This approach provides practical usability whenever model-assisted tie-breaking is unavailable, thus ensuring that multiple simulation executions provide deterministic behaviour and repeatable results. Moreover, it ensures that the selected order of events is also consistent with sequential executions. We discuss the theory behind this strategy and experimentally show that the performance drop is imputable to event queue management when relying on tie-breaking strategies like the ones discussed in this work.